var FUNC_ERROR_TEXT = "Expected a function";

var NAN = 0 / 0;

var symbolTag = "[object Symbol]";

var reTrim = /^\s+|\s+$/g;

var reIsBadHex = /^[-+]0x[0-9a-f]+$/i;

var reIsBinary = /^0b[01]+$/i;

var reIsOctal = /^0o[0-7]+$/i;

var freeParseInt = parseInt;

var objectProto = Object.prototype;

var objectToString = objectProto.toString;

var nativeMax = Math.max,
  nativeMin = Math.min;

var now = function () {
  return Date.now();
};

function debounce(func, wait, options) {
  var lastArgs,
    lastThis,
    maxWait,
    result,
    timerId,
    lastCallTime,
    lastInvokeTime = 0,
    leading = false,
    maxing = false,
    trailing = true;

  if (typeof func != "function") {
    throw new TypeError(FUNC_ERROR_TEXT);
  }
  wait = toNumber(wait) || 0;
  if (isObject(options)) {
    leading = !!options.leading;
    maxing = "maxWait" in options;
    maxWait = maxing
      ? nativeMax(toNumber(options.maxWait) || 0, wait)
      : maxWait;
    trailing = "trailing" in options ? !!options.trailing : trailing;
  }

  function invokeFunc(time) {
    var args = lastArgs,
      thisArg = lastThis;

    lastArgs = lastThis = undefined;
    lastInvokeTime = time;
    result = func.apply(thisArg, args);
    return result;
  }

  function leadingEdge(time) {
    lastInvokeTime = time;
    timerId = setTimeout(timerExpired, wait);
    return leading ? invokeFunc(time) : result;
  }

  function remainingWait(time) {
    var timeSinceLastCall = time - lastCallTime,
      timeSinceLastInvoke = time - lastInvokeTime,
      result = wait - timeSinceLastCall;

    return maxing ? nativeMin(result, maxWait - timeSinceLastInvoke) : result;
  }

  function shouldInvoke(time) {
    var timeSinceLastCall = time - lastCallTime,
      timeSinceLastInvoke = time - lastInvokeTime;

    return (
      lastCallTime === undefined ||
      timeSinceLastCall >= wait ||
      timeSinceLastCall < 0 ||
      (maxing && timeSinceLastInvoke >= maxWait)
    );
  }

  function timerExpired() {
    var time = now();
    if (shouldInvoke(time)) {
      return trailingEdge(time);
    }
    timerId = setTimeout(timerExpired, remainingWait(time));
  }

  function trailingEdge(time) {
    timerId = undefined;
    if (trailing && lastArgs) {
      return invokeFunc(time);
    }
    lastArgs = lastThis = undefined;
    return result;
  }

  function cancel() {
    if (timerId !== undefined) {
      clearTimeout(timerId);
    }
    lastInvokeTime = 0;
    lastArgs = lastCallTime = lastThis = timerId = undefined;
  }

  function flush() {
    return timerId === undefined ? result : trailingEdge(now());
  }

  function debounced() {
    var time = now(),
      isInvoking = shouldInvoke(time);

    lastArgs = arguments;
    lastThis = this;
    lastCallTime = time;

    if (isInvoking) {
      if (timerId === undefined) {
        return leadingEdge(lastCallTime);
      }
      if (maxing) {
        timerId = setTimeout(timerExpired, wait);
        return invokeFunc(lastCallTime);
      }
    }
    if (timerId === undefined) {
      timerId = setTimeout(timerExpired, wait);
    }
    return result;
  }
  debounced.cancel = cancel;
  debounced.flush = flush;
  return debounced;
}

function throttle(func, wait, options) {
  var leading = true,
    trailing = true;

  if (typeof func != "function") {
    throw new TypeError(FUNC_ERROR_TEXT);
  }
  if (isObject(options)) {
    leading = "leading" in options ? !!options.leading : leading;
    trailing = "trailing" in options ? !!options.trailing : trailing;
  }
  return debounce(func, wait, {
    leading: leading,
    maxWait: wait,
    trailing: trailing,
  });
}
function isObject(value) {
  var type = typeof value;
  return !!value && (type == "object" || type == "function");
}

function isObjectLike(value) {
  return !!value && typeof value == "object";
}

function isSymbol(value) {
  return (
    typeof value == "symbol" ||
    (isObjectLike(value) && objectToString.call(value) == symbolTag)
  );
}

function toNumber(value) {
  if (typeof value == "number") {
    return value;
  }
  if (isSymbol(value)) {
    return NAN;
  }
  if (isObject(value)) {
    var other = typeof value.valueOf == "function" ? value.valueOf() : value;
    value = isObject(other) ? other + "" : other;
  }
  if (typeof value != "string") {
    return value === 0 ? value : +value;
  }
  value = value.replace(reTrim, "");
  var isBinary = reIsBinary.test(value);
  return isBinary || reIsOctal.test(value)
    ? freeParseInt(value.slice(2), isBinary ? 2 : 8)
    : reIsBadHex.test(value)
    ? NAN
    : +value;
}

export {
  throttle,
  debounce,
};
